12739981 has 8 divisors (see below), whose sum is σ = 13042944. Its totient is φ = 12439440.

The previous prime is 12739973. The next prime is 12740003. The reversal of 12739981 is 18993721.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12739981 - 2³ = 12739973 is a prime.

It is a super-2 number, since 2×12739981² = 324614231760722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12739931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13920 + ... + 14806.

It is an arithmetic number, because the mean of its divisors is an integer number (1630368).

Almost surely, 2^12739981 is an apocalyptic number.

It is an amenable number.

12739981 is a deficient number, since it is larger than the sum of its proper divisors (302963).

12739981 is an equidigital number, since it uses as much as digits as its factorization.

12739981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1211.

The product of its digits is 27216, while the sum is 40.

The square root of 12739981 is about 3569.3109979378. The cubic root of 12739981 is about 233.5552281451. Note that the first 3 decimals are identical.

The spelling of 12739981 in words is "twelve million, seven hundred thirty-nine thousand, nine hundred eighty-one".